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Postmortem changes at 5C in myofibrillar proteins of longissimus dorsi (LD), biceps femoris (BF), semimembranosus (SM) and semitendinosus (ST) muscles and myofibrillar structure of LD muscle of goat were investigated. Muscle samples were immediately collected after killing, and from carcasses stored at 5C for 3, 6, 9, 12 and 20 days. The sodium dodecyl sulfate‐polyacrylamide gel electrophoresis of myofibrils indicated the appearance of a 30 kDa component, depending on the type of the muscles. A new 55 kDa component appeared in BF and SM muscles during postmortem. Titin I and nebulin also disappeared during storage. The disappearance of titin 1 and nebulin and the appearance of a 30 kDa component were confirmed by Western blot analysis. The Transmission Electron Microscopy studies showed that after 3 days postmortem, Z‐disks stayed unaltered. After 6 days postmortem, a little ultrastructural alteration was observed, and at 12 days postmortem a considerable degradation of Z‐disk ultrastructure was shown. The Z‐disk degradation, which results in the fragmentation of myofibrils and the appearance of 30 kDa components, is the major change observed in goat skeletal muscles during postmortem.

The dietary fibers were mainly isolated from seed hull of field beans (Phaseolus vulgaris), waste pulp of pineapple (Ananas camosus) as well as from whole wheat flour and, the fiber yields were 16.8, 2.0 and 7.0g/100g, respectively. These isolated fibers were included in sponge cake preparation by partially replacing all‐purpose flour (maida) by 5% (w/w). Cakes and cake batter were evaluated for pH change, specific gravity, volume, moisture content, and color. The sensory characteristics and volume of the cakes were not altered with the inclusion of isolated fiber in the cake. The sensory quality evaluation showed that the fiber incorporated cakes were acceptable similar to the cake without added fiber. Incorporation of various fibers in the cake preparation increased the total dietary fiber content of the product by 4‐6%.

The objective of this study was to elucidate a relationship between some endogenous proteinases and their inhibitors in four different goat muscles during postmortem storage. Samples were taken from the longissimus dorsi (LD), biceps femoris (BF), semimembranosus (SM) and semitendinosus (ST) muscles stored up to 20 days postmortem at 5C. Activities of calpain‐I, calpain‐II, calpastatin, cathepsins (B, B+L, H and D) and cystatin(s) were determined. Decreases in calpain‐I and calpastatin activities were significantly more than that of calpain‐II activity. The cathepsin B, B+L, H and cystatin level were found to fall by 9–35 % after 20 days, whereas the cathepsin D showed 11–17% decline in all the muscles. Thus changes in muscle proteinases and their inhibitors during postmortem storage differ and the results may shed light on their role in myofibrillar proteolysis and goat meat tenderization.